IO-AIO/AIO.xs

#define _REENTRANT 1
#include <errno.h>

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include "autoconf/config.h"

#include <pthread.h>

#include <stddef.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <limits.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sched.h>

#if HAVE_SENDFILE
# if __linux
#  include <sys/sendfile.h>
# elif __freebsd
#  include <sys/socket.h>
#  include <sys/uio.h>
# elif __hpux
#  include <sys/socket.h>
# elif __solaris /* not yet */
#  include <sys/sendfile.h>
# else
#  error sendfile support requested but not available
# endif
#endif

/* used for struct dirent, AIX doesn't provide it */
#ifndef NAME_MAX
# define NAME_MAX 4096
#endif

#if __ia64
# define STACKSIZE 65536
#else
# define STACKSIZE  8192
#endif

enum {
  REQ_QUIT,
  REQ_OPEN, REQ_CLOSE,
  REQ_READ, REQ_WRITE, REQ_READAHEAD,
  REQ_SENDFILE,
  REQ_STAT, REQ_LSTAT, REQ_FSTAT,
  REQ_FSYNC, REQ_FDATASYNC,
  REQ_UNLINK, REQ_RMDIR, REQ_RENAME,
  REQ_READDIR,
  REQ_LINK, REQ_SYMLINK,
};

typedef struct aio_cb {
  struct aio_cb *volatile next;

  int type;

  /* should receive a cleanup, with unions */
  int fd, fd2;
  off_t offset;
  size_t length;
  ssize_t result;
  mode_t mode; /* open */
  int errorno;
  SV *data, *callback;
  SV *fh, *fh2;
  void *dataptr, *data2ptr;
  STRLEN dataoffset;

  Stat_t *statdata;
} aio_cb;

typedef aio_cb *aio_req;

static int started, wanted;
static volatile int nreqs;
static int max_outstanding = 1<<30;
static int respipe [2];

static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
static pthread_cond_t  reqwait = PTHREAD_COND_INITIALIZER;

static volatile aio_req reqs, reqe; /* queue start, queue end */
static volatile aio_req ress, rese; /* queue start, queue end */

static void free_req (aio_req req)
{
  if (req->data)
    SvREFCNT_dec (req->data);

  if (req->fh)
    SvREFCNT_dec (req->fh);

  if (req->fh2)
    SvREFCNT_dec (req->fh2);

  if (req->statdata)
    Safefree (req->statdata);

  if (req->callback)
    SvREFCNT_dec (req->callback);

  if (req->type == REQ_READDIR && req->result >= 0)
    free (req->data2ptr);

  Safefree (req);
}

static void
poll_wait ()
{
  if (nreqs && !ress)
    {
      fd_set rfd;
      FD_ZERO(&rfd);
      FD_SET(respipe [0], &rfd);

      select (respipe [0] + 1, &rfd, 0, 0, 0);
    }
}

static int
poll_cb ()
{
  dSP;
  int count = 0;
  int do_croak = 0;
  aio_req req;

  for (;;)
    {
      pthread_mutex_lock (&reslock);
      req = ress;

      if (req)
        {
          ress = req->next;

          if (!ress)
            {
              /* read any signals sent by the worker threads */
              char buf [32];
              while (read (respipe [0], buf, 32) == 32)
                ;

              rese = 0;
            }
        }

      pthread_mutex_unlock (&reslock);

      if (!req)
        break;

      nreqs--;

      if (req->type == REQ_QUIT)
        started--;
      else
        {
          int errorno = errno;
          errno = req->errorno;

          if (req->type == REQ_READ)
            SvCUR_set (req->data, req->dataoffset + (req->result > 0 ? req->result : 0));

          if (req->data2ptr && (req->type == REQ_READ || req->type == REQ_WRITE))
            SvREADONLY_off (req->data);

          if (req->statdata)
            {
              PL_laststype   = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
              PL_laststatval = req->result;
              PL_statcache   = *(req->statdata);
            }

          ENTER;
          PUSHMARK (SP);

          if (req->type == REQ_READDIR)
            {
              SV *rv = &PL_sv_undef;

              if (req->result >= 0)
                {
                  char *buf = req->data2ptr;
                  AV *av = newAV ();

                  while (req->result)
                    {
                      SV *sv = newSVpv (buf, 0);

                      av_push (av, sv);
                      buf += SvCUR (sv) + 1;
                      req->result--;
                    }

                  rv = sv_2mortal (newRV_noinc ((SV *)av));
                }

              XPUSHs (rv);
            }
          else
            {
              XPUSHs (sv_2mortal (newSViv (req->result)));

              if (req->type == REQ_OPEN)
                {
                  /* convert fd to fh */
                  SV *fh;

                  PUTBACK;
                  call_pv ("IO::AIO::_fd2fh", G_SCALAR | G_EVAL);
                  SPAGAIN;

                  fh = SvREFCNT_inc (POPs);

                  PUSHMARK (SP);
                  XPUSHs (sv_2mortal (fh));
                }
            }

          if (SvOK (req->callback))
            {
              PUTBACK;
              call_sv (req->callback, G_VOID | G_EVAL);
              SPAGAIN;

              if (SvTRUE (ERRSV))
                {
                  free_req (req);
                  croak (0);
                }
            }

          LEAVE;

          errno = errorno;
          count++;
        }

      free_req (req);
    }

  return count;
}

static void *aio_proc(void *arg);

static void
start_thread (void)
{
  sigset_t fullsigset, oldsigset;
  pthread_t tid;
  pthread_attr_t attr;

  pthread_attr_init (&attr);
  pthread_attr_setstacksize (&attr, STACKSIZE);
  pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);

  sigfillset (&fullsigset);
  sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);

  if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
    started++;

  sigprocmask (SIG_SETMASK, &oldsigset, 0);
}

static void
send_req (aio_req req)
{
  while (started < wanted && nreqs >= started)
    start_thread ();

  nreqs++;

  pthread_mutex_lock (&reqlock);

  req->next = 0;

  if (reqe)
    {
      reqe->next = req;
      reqe = req;
    }
  else
    reqe = reqs = req;

  pthread_cond_signal (&reqwait);
  pthread_mutex_unlock (&reqlock);

  if (nreqs > max_outstanding)
    for (;;)
      {
        poll_cb ();

        if (nreqs <= max_outstanding)
          break;

        poll_wait ();
      }
}

static void
end_thread (void)
{
  aio_req req;
  Newz (0, req, 1, aio_cb);
  req->type = REQ_QUIT;

  send_req (req);
}

static void min_parallel (int nthreads)
{
  if (wanted < nthreads)
    wanted = nthreads;
}

static void max_parallel (int nthreads)
{
  int cur = started;

  if (wanted > nthreads)
    wanted = nthreads;

  while (cur > wanted)
    {
      end_thread ();
      cur--;
    }

  while (started > wanted)
    {
      poll_wait ();
      poll_cb ();
    }
}

static void create_pipe ()
{
  if (pipe (respipe))
    croak ("unable to initialize result pipe");

  if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
    croak ("cannot set result pipe to nonblocking mode");

  if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
    croak ("cannot set result pipe to nonblocking mode");
}

/*****************************************************************************/
/* work around various missing functions */

#if !HAVE_PREADWRITE
# define pread  aio_pread
# define pwrite aio_pwrite

/*
 * make our pread/pwrite safe against themselves, but not against
 * normal read/write by using a mutex. slows down execution a lot,
 * but that's your problem, not mine.
 */
static pthread_mutex_t preadwritelock = PTHREAD_MUTEX_INITIALIZER;

static ssize_t
pread (int fd, void *buf, size_t count, off_t offset)
{
  ssize_t res;
  off_t ooffset;

  pthread_mutex_lock (&preadwritelock);
  ooffset = lseek (fd, 0, SEEK_CUR);
  lseek (fd, offset, SEEK_SET);
  res = read (fd, buf, count);
  lseek (fd, ooffset, SEEK_SET);
  pthread_mutex_unlock (&preadwritelock);

  return res;
}

static ssize_t
pwrite (int fd, void *buf, size_t count, off_t offset)
{
  ssize_t res;
  off_t ooffset;

  pthread_mutex_lock (&preadwritelock);
  ooffset = lseek (fd, 0, SEEK_CUR);
  lseek (fd, offset, SEEK_SET);
  res = write (fd, buf, count);
  lseek (fd, offset, SEEK_SET);
  pthread_mutex_unlock (&preadwritelock);

  return res;
}
#endif

#if !HAVE_FDATASYNC
# define fdatasync fsync
#endif

#if !HAVE_READAHEAD
# define readahead aio_readahead

static ssize_t
readahead (int fd, off_t offset, size_t count)
{
  char readahead_buf[4096];

  while (count > 0)
    {
      size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);

      pread (fd, readahead_buf, len, offset);
      offset += len;
      count  -= len;
    }

  errno = 0;
}
#endif

#if !HAVE_READDIR_R
# define readdir_r aio_readdir_r

static pthread_mutex_t readdirlock = PTHREAD_MUTEX_INITIALIZER;
  
static int
readdir_r (DIR *dirp, struct dirent *ent, struct dirent **res)
{
  struct dirent *e;
  int errorno;

  pthread_mutex_lock (&readdirlock);

  e = readdir (dirp);
  errorno = errno;

  if (e)
    {
      *res = ent;
      strcpy (ent->d_name, e->d_name);
    }
  else
    *res = 0;

  pthread_mutex_unlock (&readdirlock);

  errno = errorno;
  return e ? 0 : -1;
}
#endif

/* sendfile always needs emulation */
static ssize_t
sendfile_ (int ofd, int ifd, off_t offset, size_t count)
{
  ssize_t res;

  if (!count)
    return 0;

#if HAVE_SENDFILE
# if __linux
  res = sendfile (ofd, ifd, &offset, count);

# elif __freebsd
  /*
   * Of course, the freebsd sendfile is a dire hack with no thoughts
   * wasted on making it similar to other I/O functions.
   */
  {
    off_t sbytes;
    res = sendfile (ifd, ofd, offset, count, 0, &sbytes, 0);

    if (res < 0 && sbytes)
      /* maybe only on EAGAIN only: as usual, the manpage leaves you guessing */
      res = sbytes;
  }

# elif __hpux
  res = sendfile (ofd, ifd, offset, count, 0, 0);

# elif __solaris
  {
    struct sendfilevec vec;
    size_t sbytes;

    vec.sfv_fd   = ifd;
    vec.sfv_flag = 0;
    vec.sfv_off  = offset;
    vec.sfv_len  = count;

    res = sendfilev (ofd, &vec, 1, &sbytes);

    if (res < 0 && sbytes)
      res = sbytes;
  }

# endif
#else
  res = -1;
  errno = ENOSYS;
#endif

  if (res <  0
      && (errno == ENOSYS || errno == EINVAL || errno == ENOTSOCK
#if __solaris
          || errno == EAFNOSUPPORT || errno == EPROTOTYPE
#endif
         )
      )
    {
      /* emulate sendfile. this is a major pain in the ass */
      char buf[4096];
      res = 0;

      while (count)
        {
          ssize_t cnt;
          
          cnt = pread (ifd, buf, count > 4096 ? 4096 : count, offset);

          if (cnt <= 0)
            {
              if (cnt && !res) res = -1;
              break;
            }

          cnt = write (ofd, buf, cnt);

          if (cnt <= 0)
            {
              if (cnt && !res) res = -1;
              break;
            }

          offset += cnt;
          res    += cnt;
          count  -= cnt;
        }
    }

  return res;
}

/* read a full directory */
static int
scandir_ (const char *path, void **namesp)
{
  DIR *dirp = opendir (path);
  union
  {    
    struct dirent d;
    char b [offsetof (struct dirent, d_name) + NAME_MAX + 1];
  } u;
  struct dirent *entp;
  char *name, *names;
  int memlen = 4096;
  int memofs = 0;
  int res = 0;
  int errorno;

  if (!dirp)
    return -1;

  names = malloc (memlen);

  for (;;)
    {
      errno = 0, readdir_r (dirp, &u.d, &entp);

      if (!entp)
        break;

      name = entp->d_name;

      if (name [0] != '.' || (name [1] && (name [1] != '.' || name [2])))
        {
          int len = strlen (name) + 1;

          res++;

          while (memofs + len > memlen)
            {
              memlen *= 2;
              names = realloc (names, memlen);
              if (!names)
                break;
            }

          memcpy (names + memofs, name, len);
          memofs += len;
        }
    }

  errorno = errno;
  closedir (dirp);

  if (errorno)
    {
      free (names);
      errno = errorno;
      res = -1;
    }

  *namesp = (void *)names;
  return res;
}

/*****************************************************************************/

static void *
aio_proc (void *thr_arg)
{
  aio_req req;
  int type;

  do
    {
      pthread_mutex_lock (&reqlock);

      for (;;)
        {
          req = reqs;

          if (reqs)
            {
              reqs = reqs->next;
              if (!reqs) reqe = 0;
            }

          if (req)
            break;

          pthread_cond_wait (&reqwait, &reqlock);
        }

      pthread_mutex_unlock (&reqlock);
     
      errno = 0; /* strictly unnecessary */

      type = req->type;

      switch (type)
        {
          case REQ_READ:      req->result = pread     (req->fd, req->dataptr, req->length, req->offset); break;
          case REQ_WRITE:     req->result = pwrite    (req->fd, req->dataptr, req->length, req->offset); break;

          case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
          case REQ_SENDFILE:  req->result = sendfile_ (req->fd, req->fd2, req->offset, req->length); break;

          case REQ_STAT:      req->result = stat      (req->dataptr, req->statdata); break;
          case REQ_LSTAT:     req->result = lstat     (req->dataptr, req->statdata); break;
          case REQ_FSTAT:     req->result = fstat     (req->fd     , req->statdata); break;

          case REQ_OPEN:      req->result = open      (req->dataptr, req->fd, req->mode); break;
          case REQ_CLOSE:     req->result = close     (req->fd); break;
          case REQ_UNLINK:    req->result = unlink    (req->dataptr); break;
          case REQ_RMDIR:     req->result = rmdir     (req->dataptr); break;
          case REQ_RENAME:    req->result = rename    (req->data2ptr, req->dataptr); break;
          case REQ_LINK:      req->result = link      (req->data2ptr, req->dataptr); break;
          case REQ_SYMLINK:   req->result = symlink   (req->data2ptr, req->dataptr); break;

          case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
          case REQ_FSYNC:     req->result = fsync     (req->fd); break;
          case REQ_READDIR:   req->result = scandir_  (req->dataptr, &req->data2ptr); break;

          case REQ_QUIT:
            break;

          default:
            req->result = ENOSYS;
            break;
        }

      req->errorno = errno;

      pthread_mutex_lock (&reslock);

      req->next = 0;

      if (rese)
        {
          rese->next = req;
          rese = req;
        }
      else
        {
          rese = ress = req;

          /* write a dummy byte to the pipe so fh becomes ready */
          write (respipe [1], &respipe, 1);
        }

      pthread_mutex_unlock (&reslock);
    }
  while (type != REQ_QUIT);

  return 0;
}

/*****************************************************************************/

static void atfork_prepare (void)
{
  pthread_mutex_lock (&reqlock);
  pthread_mutex_lock (&reslock);
#if !HAVE_PREADWRITE
  pthread_mutex_lock (&preadwritelock);
#endif
#if !HAVE_READDIR_R
  pthread_mutex_lock (&readdirlock);
#endif
}

static void atfork_parent (void)
{
#if !HAVE_READDIR_R
  pthread_mutex_unlock (&readdirlock);
#endif
#if !HAVE_PREADWRITE
  pthread_mutex_unlock (&preadwritelock);
#endif
  pthread_mutex_unlock (&reslock);
  pthread_mutex_unlock (&reqlock);
}

static void atfork_child (void)
{
  aio_req prv;

  started = 0;

  while (reqs)
    {
      prv = reqs;
      reqs = prv->next;
      free_req (prv);
    }

  reqs = reqe = 0;
      
  while (ress)
    {
      prv = ress;
      ress = prv->next;
      free_req (prv);
    }
      
  ress = rese = 0;

  close (respipe [0]);
  close (respipe [1]);
  create_pipe ();

  atfork_parent ();
}

#define dREQ                                                    \
  aio_req req;                                                  \
                                                                \
  if (SvOK (callback) && !SvROK (callback))                     \
    croak ("clalback must be undef or of reference type");      \
                                                                \
  Newz (0, req, 1, aio_cb);                                     \
  if (!req)                                                     \
    croak ("out of memory during aio_req allocation");          \
                                                                \
  req->callback = newSVsv (callback);
        
MODULE = IO::AIO                PACKAGE = IO::AIO

PROTOTYPES: ENABLE

BOOT:
{
        HV *stash = gv_stashpv ("IO::AIO", 1);
        newCONSTSUB (stash, "EXDEV",    newSViv (EXDEV));
        newCONSTSUB (stash, "O_RDONLY", newSViv (O_RDONLY));
        newCONSTSUB (stash, "O_WRONLY", newSViv (O_WRONLY));

        create_pipe ();
        pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
}

void
min_parallel (nthreads)
        int     nthreads
        PROTOTYPE: $

void
max_parallel (nthreads)
        int     nthreads
        PROTOTYPE: $

int
max_outstanding (nreqs)
        int nreqs
        PROTOTYPE: $
        CODE:
        RETVAL = max_outstanding;
        max_outstanding = nreqs;

void
aio_open (pathname,flags,mode,callback=&PL_sv_undef)
        SV *    pathname
        int     flags
        int     mode
        SV *    callback
        PROTOTYPE: $$$;$
        CODE:
{
        dREQ;

        req->type = REQ_OPEN;
        req->data = newSVsv (pathname);
        req->dataptr = SvPVbyte_nolen (req->data);
        req->fd = flags;
        req->mode = mode;

        send_req (req);
}

void
aio_close (fh,callback=&PL_sv_undef)
        SV *    fh
        SV *    callback
        PROTOTYPE: $;$
        ALIAS:
           aio_close     = REQ_CLOSE
           aio_fsync     = REQ_FSYNC
           aio_fdatasync = REQ_FDATASYNC
        CODE:
{
        dREQ;

        req->type = ix;
        req->fh = newSVsv (fh);
        req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));

        send_req (req);
}

void
aio_read (fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
        SV *    fh
        UV      offset
        UV      length
        SV *    data
        UV      dataoffset
        SV *    callback
        ALIAS:
           aio_read  = REQ_READ
           aio_write = REQ_WRITE
        PROTOTYPE: $$$$$;$
        CODE:
{
        aio_req req;
        STRLEN svlen;
        char *svptr = SvPVbyte (data, svlen);

        SvUPGRADE (data, SVt_PV);
        SvPOK_on (data);

        if (dataoffset < 0)
          dataoffset += svlen;

        if (dataoffset < 0 || dataoffset > svlen)
          croak ("data offset outside of string");

        if (ix == REQ_WRITE)
          {
            /* write: check length and adjust. */
            if (length < 0 || length + dataoffset > svlen)
              length = svlen - dataoffset;
          }
        else
          {
            /* read: grow scalar as necessary */
            svptr = SvGROW (data, length + dataoffset);
          }

        if (length < 0)
          croak ("length must not be negative");

        {
          dREQ;

          req->type = ix;
          req->fh = newSVsv (fh);
          req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
                                                  : IoOFP (sv_2io (fh)));
          req->offset = offset;
          req->length = length;
          req->data = SvREFCNT_inc (data);
          req->dataptr = (char *)svptr + dataoffset;

          if (!SvREADONLY (data))
            {
              SvREADONLY_on (data);
              req->data2ptr = (void *)data;
            }

          send_req (req);
        }
}

void
aio_sendfile (out_fh,in_fh,in_offset,length,callback=&PL_sv_undef)
        SV *    out_fh
        SV *    in_fh
        UV      in_offset
        UV      length
        SV *    callback
        PROTOTYPE: $$$$;$
        CODE:
{
        dREQ;

        req->type = REQ_SENDFILE;
        req->fh = newSVsv (out_fh);
        req->fd = PerlIO_fileno (IoIFP (sv_2io (out_fh)));
        req->fh2 = newSVsv (in_fh);
        req->fd2 = PerlIO_fileno (IoIFP (sv_2io (in_fh)));
        req->offset = in_offset;
        req->length = length;

        send_req (req);
}

void
aio_readahead (fh,offset,length,callback=&PL_sv_undef)
        SV *    fh
        UV      offset
        IV      length
        SV *    callback
        PROTOTYPE: $$$;$
        CODE:
{
        dREQ;

        req->type = REQ_READAHEAD;
        req->fh = newSVsv (fh);
        req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
        req->offset = offset;
        req->length = length;

        send_req (req);
}

void
aio_stat (fh_or_path,callback=&PL_sv_undef)
        SV *            fh_or_path
        SV *            callback
        ALIAS:
           aio_stat  = REQ_STAT
           aio_lstat = REQ_LSTAT
        CODE:
{
        dREQ;

        New (0, req->statdata, 1, Stat_t);
        if (!req->statdata)
          {
            free_req (req);
            croak ("out of memory during aio_req->statdata allocation");
          }

        if (SvPOK (fh_or_path))
          {
            req->type = ix;
            req->data = newSVsv (fh_or_path);
            req->dataptr = SvPVbyte_nolen (req->data);
          }
        else
          {
            req->type = REQ_FSTAT;
            req->fh = newSVsv (fh_or_path);
            req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
          }

        send_req (req);
}

void
aio_unlink (pathname,callback=&PL_sv_undef)
        SV * pathname
        SV * callback
        ALIAS:
           aio_unlink  = REQ_UNLINK
           aio_rmdir   = REQ_RMDIR
           aio_readdir = REQ_READDIR
        CODE:
{
        dREQ;
        
        req->type = ix;
        req->data = newSVsv (pathname);
        req->dataptr = SvPVbyte_nolen (req->data);
        
        send_req (req);
}

void
aio_link (oldpath,newpath,callback=&PL_sv_undef)
        SV * oldpath
        SV * newpath
        SV * callback
        ALIAS:
           aio_link    = REQ_LINK
           aio_symlink = REQ_SYMLINK
           aio_rename  = REQ_RENAME
        CODE:
{
        dREQ;
        
        req->type = ix;
        req->fh = newSVsv (oldpath);
        req->data2ptr = SvPVbyte_nolen (req->fh);
        req->data = newSVsv (newpath);
        req->dataptr = SvPVbyte_nolen (req->data);
        
        send_req (req);
}

void
flush ()
        PROTOTYPE:
        CODE:
        while (nreqs)
          {
            poll_wait ();
            poll_cb ();
          }

void
poll()
        PROTOTYPE:
        CODE:
        if (nreqs)
          {
            poll_wait ();
            poll_cb ();
          }

int
poll_fileno()
        PROTOTYPE:
        CODE:
        RETVAL = respipe [0];
        OUTPUT:
        RETVAL

int
poll_cb(...)
        PROTOTYPE:
        CODE:
        RETVAL = poll_cb ();
        OUTPUT:
        RETVAL

void
poll_wait()
        PROTOTYPE:
        CODE:
        if (nreqs)
          poll_wait ();

int
nreqs()
        PROTOTYPE:
        CODE:
        RETVAL = nreqs;
        OUTPUT:
        RETVAL

Revision:	1.41
Committed:	Sat Jun 24 19:14:04 2006 UTC (17 years, 10 months ago) by root
Branch:	MAIN
CVS Tags:	rel-1_8
Changes since 1.40:	+6 -0 lines
Log Message:	* empty log message *
#	Content
1	#define _REENTRANT 1
2	#include <errno.h>
3
4	#include "EXTERN.h"
5	#include "perl.h"
6	#include "XSUB.h"
7
8	#include "autoconf/config.h"
9
10	#include <pthread.h>
11
12	#include <stddef.h>
13	#include <errno.h>
14	#include <sys/types.h>
15	#include <sys/stat.h>
16	#include <limits.h>
17	#include <unistd.h>
18	#include <fcntl.h>
19	#include <signal.h>
20	#include <sched.h>
21
22	#if HAVE_SENDFILE
23	# if __linux
24	# include <sys/sendfile.h>
25	# elif __freebsd
26	# include <sys/socket.h>
27	# include <sys/uio.h>
28	# elif __hpux
29	# include <sys/socket.h>
30	# elif __solaris /* not yet */
31	# include <sys/sendfile.h>
32	# else
33	# error sendfile support requested but not available
34	# endif
35	#endif
36
37	/* used for struct dirent, AIX doesn't provide it */
38	#ifndef NAME_MAX
39	# define NAME_MAX 4096
40	#endif
41
42	#if __ia64
43	# define STACKSIZE 65536
44	#else
45	# define STACKSIZE 8192
46	#endif
47
48	enum {
49	REQ_QUIT,
50	REQ_OPEN, REQ_CLOSE,
51	REQ_READ, REQ_WRITE, REQ_READAHEAD,
52	REQ_SENDFILE,
53	REQ_STAT, REQ_LSTAT, REQ_FSTAT,
54	REQ_FSYNC, REQ_FDATASYNC,
55	REQ_UNLINK, REQ_RMDIR, REQ_RENAME,
56	REQ_READDIR,
57	REQ_LINK, REQ_SYMLINK,
58	};
59
60	typedef struct aio_cb {
61	struct aio_cb *volatile next;
62
63	int type;
64
65	/* should receive a cleanup, with unions */
66	int fd, fd2;
67	off_t offset;
68	size_t length;
69	ssize_t result;
70	mode_t mode; /* open */
71	int errorno;
72	SV data, callback;
73	SV fh, fh2;
74	void dataptr, data2ptr;
75	STRLEN dataoffset;
76
77	Stat_t *statdata;
78	} aio_cb;
79
80	typedef aio_cb *aio_req;
81
82	static int started, wanted;
83	static volatile int nreqs;
84	static int max_outstanding = 1<<30;
85	static int respipe [2];
86
87	static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
88	static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
89	static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
90
91	static volatile aio_req reqs, reqe; /* queue start, queue end */
92	static volatile aio_req ress, rese; /* queue start, queue end */
93
94	static void free_req (aio_req req)
95	{
96	if (req->data)
97	SvREFCNT_dec (req->data);
98
99	if (req->fh)
100	SvREFCNT_dec (req->fh);
101
102	if (req->fh2)
103	SvREFCNT_dec (req->fh2);
104
105	if (req->statdata)
106	Safefree (req->statdata);
107
108	if (req->callback)
109	SvREFCNT_dec (req->callback);
110
111	if (req->type == REQ_READDIR && req->result >= 0)
112	free (req->data2ptr);
113
114	Safefree (req);
115	}
116
117	static void
118	poll_wait ()
119	{
120	if (nreqs && !ress)
121	{
122	fd_set rfd;
123	FD_ZERO(&rfd);
124	FD_SET(respipe [0], &rfd);
125
126	select (respipe [0] + 1, &rfd, 0, 0, 0);
127	}
128	}
129
130	static int
131	poll_cb ()
132	{
133	dSP;
134	int count = 0;
135	int do_croak = 0;
136	aio_req req;
137
138	for (;;)
139	{
140	pthread_mutex_lock (&reslock);
141	req = ress;
142
143	if (req)
144	{
145	ress = req->next;
146
147	if (!ress)
148	{
149	/* read any signals sent by the worker threads */
150	char buf [32];
151	while (read (respipe [0], buf, 32) == 32)
152	;
153
154	rese = 0;
155	}
156	}
157
158	pthread_mutex_unlock (&reslock);
159
160	if (!req)
161	break;
162
163	nreqs--;
164
165	if (req->type == REQ_QUIT)
166	started--;
167	else
168	{
169	int errorno = errno;
170	errno = req->errorno;
171
172	if (req->type == REQ_READ)
173	SvCUR_set (req->data, req->dataoffset + (req->result > 0 ? req->result : 0));
174
175	if (req->data2ptr && (req->type == REQ_READ \|\| req->type == REQ_WRITE))
176	SvREADONLY_off (req->data);
177
178	if (req->statdata)
179	{
180	PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
181	PL_laststatval = req->result;
182	PL_statcache = *(req->statdata);
183	}
184
185	ENTER;
186	PUSHMARK (SP);
187
188	if (req->type == REQ_READDIR)
189	{
190	SV *rv = &PL_sv_undef;
191
192	if (req->result >= 0)
193	{
194	char *buf = req->data2ptr;
195	AV *av = newAV ();
196
197	while (req->result)
198	{
199	SV *sv = newSVpv (buf, 0);
200
201	av_push (av, sv);
202	buf += SvCUR (sv) + 1;
203	req->result--;
204	}
205
206	rv = sv_2mortal (newRV_noinc ((SV *)av));
207	}
208
209	XPUSHs (rv);
210	}
211	else
212	{
213	XPUSHs (sv_2mortal (newSViv (req->result)));
214
215	if (req->type == REQ_OPEN)
216	{
217	/* convert fd to fh */
218	SV *fh;
219
220	PUTBACK;
221	call_pv ("IO::AIO::_fd2fh", G_SCALAR \| G_EVAL);
222	SPAGAIN;
223
224	fh = SvREFCNT_inc (POPs);
225
226	PUSHMARK (SP);
227	XPUSHs (sv_2mortal (fh));
228	}
229	}
230
231	if (SvOK (req->callback))
232	{
233	PUTBACK;
234	call_sv (req->callback, G_VOID \| G_EVAL);
235	SPAGAIN;
236
237	if (SvTRUE (ERRSV))
238	{
239	free_req (req);
240	croak (0);
241	}
242	}
243
244	LEAVE;
245
246	errno = errorno;
247	count++;
248	}
249
250	free_req (req);
251	}
252
253	return count;
254	}
255
256	static void aio_proc(void arg);
257
258	static void
259	start_thread (void)
260	{
261	sigset_t fullsigset, oldsigset;
262	pthread_t tid;
263	pthread_attr_t attr;
264
265	pthread_attr_init (&attr);
266	pthread_attr_setstacksize (&attr, STACKSIZE);
267	pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
268
269	sigfillset (&fullsigset);
270	sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
271
272	if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
273	started++;
274
275	sigprocmask (SIG_SETMASK, &oldsigset, 0);
276	}
277
278	static void
279	send_req (aio_req req)
280	{
281	while (started < wanted && nreqs >= started)
282	start_thread ();
283
284	nreqs++;
285
286	pthread_mutex_lock (&reqlock);
287
288	req->next = 0;
289
290	if (reqe)
291	{
292	reqe->next = req;
293	reqe = req;
294	}
295	else
296	reqe = reqs = req;
297
298	pthread_cond_signal (&reqwait);
299	pthread_mutex_unlock (&reqlock);
300
301	if (nreqs > max_outstanding)
302	for (;;)
303	{
304	poll_cb ();
305
306	if (nreqs <= max_outstanding)
307	break;
308
309	poll_wait ();
310	}
311	}
312
313	static void
314	end_thread (void)
315	{
316	aio_req req;
317	Newz (0, req, 1, aio_cb);
318	req->type = REQ_QUIT;
319
320	send_req (req);
321	}
322
323	static void min_parallel (int nthreads)
324	{
325	if (wanted < nthreads)
326	wanted = nthreads;
327	}
328
329	static void max_parallel (int nthreads)
330	{
331	int cur = started;
332
333	if (wanted > nthreads)
334	wanted = nthreads;
335
336	while (cur > wanted)
337	{
338	end_thread ();
339	cur--;
340	}
341
342	while (started > wanted)
343	{
344	poll_wait ();
345	poll_cb ();
346	}
347	}
348
349	static void create_pipe ()
350	{
351	if (pipe (respipe))
352	croak ("unable to initialize result pipe");
353
354	if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
355	croak ("cannot set result pipe to nonblocking mode");
356
357	if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
358	croak ("cannot set result pipe to nonblocking mode");
359	}
360
361	/*****************************************************************************/
362	/* work around various missing functions */
363
364	#if !HAVE_PREADWRITE
365	# define pread aio_pread
366	# define pwrite aio_pwrite
367
368	/*
369	* make our pread/pwrite safe against themselves, but not against
370	* normal read/write by using a mutex. slows down execution a lot,
371	* but that's your problem, not mine.
372	*/
373	static pthread_mutex_t preadwritelock = PTHREAD_MUTEX_INITIALIZER;
374
375	static ssize_t
376	pread (int fd, void *buf, size_t count, off_t offset)
377	{
378	ssize_t res;
379	off_t ooffset;
380
381	pthread_mutex_lock (&preadwritelock);
382	ooffset = lseek (fd, 0, SEEK_CUR);
383	lseek (fd, offset, SEEK_SET);
384	res = read (fd, buf, count);
385	lseek (fd, ooffset, SEEK_SET);
386	pthread_mutex_unlock (&preadwritelock);
387
388	return res;
389	}
390
391	static ssize_t
392	pwrite (int fd, void *buf, size_t count, off_t offset)
393	{
394	ssize_t res;
395	off_t ooffset;
396
397	pthread_mutex_lock (&preadwritelock);
398	ooffset = lseek (fd, 0, SEEK_CUR);
399	lseek (fd, offset, SEEK_SET);
400	res = write (fd, buf, count);
401	lseek (fd, offset, SEEK_SET);
402	pthread_mutex_unlock (&preadwritelock);
403
404	return res;
405	}
406	#endif
407
408	#if !HAVE_FDATASYNC
409	# define fdatasync fsync
410	#endif
411
412	#if !HAVE_READAHEAD
413	# define readahead aio_readahead
414
415	static ssize_t
416	readahead (int fd, off_t offset, size_t count)
417	{
418	char readahead_buf[4096];
419
420	while (count > 0)
421	{
422	size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);
423
424	pread (fd, readahead_buf, len, offset);
425	offset += len;
426	count -= len;
427	}
428
429	errno = 0;
430	}
431	#endif
432
433	#if !HAVE_READDIR_R
434	# define readdir_r aio_readdir_r
435
436	static pthread_mutex_t readdirlock = PTHREAD_MUTEX_INITIALIZER;
437
438	static int
439	readdir_r (DIR dirp, struct dirent ent, struct dirent **res)
440	{
441	struct dirent *e;
442	int errorno;
443
444	pthread_mutex_lock (&readdirlock);
445
446	e = readdir (dirp);
447	errorno = errno;
448
449	if (e)
450	{
451	*res = ent;
452	strcpy (ent->d_name, e->d_name);
453	}
454	else
455	*res = 0;
456
457	pthread_mutex_unlock (&readdirlock);
458
459	errno = errorno;
460	return e ? 0 : -1;
461	}
462	#endif
463
464	/* sendfile always needs emulation */
465	static ssize_t
466	sendfile_ (int ofd, int ifd, off_t offset, size_t count)
467	{
468	ssize_t res;
469
470	if (!count)
471	return 0;
472
473	#if HAVE_SENDFILE
474	# if __linux
475	res = sendfile (ofd, ifd, &offset, count);
476
477	# elif __freebsd
478	/*
479	* Of course, the freebsd sendfile is a dire hack with no thoughts
480	* wasted on making it similar to other I/O functions.
481	*/
482	{
483	off_t sbytes;
484	res = sendfile (ifd, ofd, offset, count, 0, &sbytes, 0);
485
486	if (res < 0 && sbytes)
487	/* maybe only on EAGAIN only: as usual, the manpage leaves you guessing */
488	res = sbytes;
489	}
490
491	# elif __hpux
492	res = sendfile (ofd, ifd, offset, count, 0, 0);
493
494	# elif __solaris
495	{
496	struct sendfilevec vec;
497	size_t sbytes;
498
499	vec.sfv_fd = ifd;
500	vec.sfv_flag = 0;
501	vec.sfv_off = offset;
502	vec.sfv_len = count;
503
504	res = sendfilev (ofd, &vec, 1, &sbytes);
505
506	if (res < 0 && sbytes)
507	res = sbytes;
508	}
509
510	# endif
511	#else
512	res = -1;
513	errno = ENOSYS;
514	#endif
515
516	if (res < 0
517	&& (errno == ENOSYS \|\| errno == EINVAL \|\| errno == ENOTSOCK
518	#if __solaris
519	\|\| errno == EAFNOSUPPORT \|\| errno == EPROTOTYPE
520	#endif
521	)
522	)
523	{
524	/* emulate sendfile. this is a major pain in the ass */
525	char buf[4096];
526	res = 0;
527
528	while (count)
529	{
530	ssize_t cnt;
531
532	cnt = pread (ifd, buf, count > 4096 ? 4096 : count, offset);
533
534	if (cnt <= 0)
535	{
536	if (cnt && !res) res = -1;
537	break;
538	}
539
540	cnt = write (ofd, buf, cnt);
541
542	if (cnt <= 0)
543	{
544	if (cnt && !res) res = -1;
545	break;
546	}
547
548	offset += cnt;
549	res += cnt;
550	count -= cnt;
551	}
552	}
553
554	return res;
555	}
556
557	/* read a full directory */
558	static int
559	scandir_ (const char path, void *namesp)
560	{
561	DIR *dirp = opendir (path);
562	union
563	{
564	struct dirent d;
565	char b [offsetof (struct dirent, d_name) + NAME_MAX + 1];
566	} u;
567	struct dirent *entp;
568	char name, names;
569	int memlen = 4096;
570	int memofs = 0;
571	int res = 0;
572	int errorno;
573
574	if (!dirp)
575	return -1;
576
577	names = malloc (memlen);
578
579	for (;;)
580	{
581	errno = 0, readdir_r (dirp, &u.d, &entp);
582
583	if (!entp)
584	break;
585
586	name = entp->d_name;
587
588	if (name [0] != '.' \|\| (name [1] && (name [1] != '.' \|\| name [2])))
589	{
590	int len = strlen (name) + 1;
591
592	res++;
593
594	while (memofs + len > memlen)
595	{
596	memlen *= 2;
597	names = realloc (names, memlen);
598	if (!names)
599	break;
600	}
601
602	memcpy (names + memofs, name, len);
603	memofs += len;
604	}
605	}
606
607	errorno = errno;
608	closedir (dirp);
609
610	if (errorno)
611	{
612	free (names);
613	errno = errorno;
614	res = -1;
615	}
616
617	namesp = (void )names;
618	return res;
619	}
620
621	/*****************************************************************************/
622
623	static void *
624	aio_proc (void *thr_arg)
625	{
626	aio_req req;
627	int type;
628
629	do
630	{
631	pthread_mutex_lock (&reqlock);
632
633	for (;;)
634	{
635	req = reqs;
636
637	if (reqs)
638	{
639	reqs = reqs->next;
640	if (!reqs) reqe = 0;
641	}
642
643	if (req)
644	break;
645
646	pthread_cond_wait (&reqwait, &reqlock);
647	}
648
649	pthread_mutex_unlock (&reqlock);
650
651	errno = 0; /* strictly unnecessary */
652
653	type = req->type;
654
655	switch (type)
656	{
657	case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
658	case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
659
660	case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
661	case REQ_SENDFILE: req->result = sendfile_ (req->fd, req->fd2, req->offset, req->length); break;
662
663	case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
664	case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
665	case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
666
667	case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
668	case REQ_CLOSE: req->result = close (req->fd); break;
669	case REQ_UNLINK: req->result = unlink (req->dataptr); break;
670	case REQ_RMDIR: req->result = rmdir (req->dataptr); break;
671	case REQ_RENAME: req->result = rename (req->data2ptr, req->dataptr); break;
672	case REQ_LINK: req->result = link (req->data2ptr, req->dataptr); break;
673	case REQ_SYMLINK: req->result = symlink (req->data2ptr, req->dataptr); break;
674
675	case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
676	case REQ_FSYNC: req->result = fsync (req->fd); break;
677	case REQ_READDIR: req->result = scandir_ (req->dataptr, &req->data2ptr); break;
678
679	case REQ_QUIT:
680	break;
681
682	default:
683	req->result = ENOSYS;
684	break;
685	}
686
687	req->errorno = errno;
688
689	pthread_mutex_lock (&reslock);
690
691	req->next = 0;
692
693	if (rese)
694	{
695	rese->next = req;
696	rese = req;
697	}
698	else
699	{
700	rese = ress = req;
701
702	/* write a dummy byte to the pipe so fh becomes ready */
703	write (respipe [1], &respipe, 1);
704	}
705
706	pthread_mutex_unlock (&reslock);
707	}
708	while (type != REQ_QUIT);
709
710	return 0;
711	}
712
713	/*****************************************************************************/
714
715	static void atfork_prepare (void)
716	{
717	pthread_mutex_lock (&reqlock);
718	pthread_mutex_lock (&reslock);
719	#if !HAVE_PREADWRITE
720	pthread_mutex_lock (&preadwritelock);
721	#endif
722	#if !HAVE_READDIR_R
723	pthread_mutex_lock (&readdirlock);
724	#endif
725	}
726
727	static void atfork_parent (void)
728	{
729	#if !HAVE_READDIR_R
730	pthread_mutex_unlock (&readdirlock);
731	#endif
732	#if !HAVE_PREADWRITE
733	pthread_mutex_unlock (&preadwritelock);
734	#endif
735	pthread_mutex_unlock (&reslock);
736	pthread_mutex_unlock (&reqlock);
737	}
738
739	static void atfork_child (void)
740	{
741	aio_req prv;
742
743	started = 0;
744
745	while (reqs)
746	{
747	prv = reqs;
748	reqs = prv->next;
749	free_req (prv);
750	}
751
752	reqs = reqe = 0;
753
754	while (ress)
755	{
756	prv = ress;
757	ress = prv->next;
758	free_req (prv);
759	}
760
761	ress = rese = 0;
762
763	close (respipe [0]);
764	close (respipe [1]);
765	create_pipe ();
766
767	atfork_parent ();
768	}
769
770	#define dREQ \
771	aio_req req; \
772	\
773	if (SvOK (callback) && !SvROK (callback)) \
774	croak ("clalback must be undef or of reference type"); \
775	\
776	Newz (0, req, 1, aio_cb); \
777	if (!req) \
778	croak ("out of memory during aio_req allocation"); \
779	\
780	req->callback = newSVsv (callback);
781
782	MODULE = IO::AIO PACKAGE = IO::AIO
783
784	PROTOTYPES: ENABLE
785
786	BOOT:
787	{
788	HV *stash = gv_stashpv ("IO::AIO", 1);
789	newCONSTSUB (stash, "EXDEV", newSViv (EXDEV));
790	newCONSTSUB (stash, "O_RDONLY", newSViv (O_RDONLY));
791	newCONSTSUB (stash, "O_WRONLY", newSViv (O_WRONLY));
792
793	create_pipe ();
794	pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
795	}
796
797	void
798	min_parallel (nthreads)
799	int nthreads
800	PROTOTYPE: $
801
802	void
803	max_parallel (nthreads)
804	int nthreads
805	PROTOTYPE: $
806
807	int
808	max_outstanding (nreqs)
809	int nreqs
810	PROTOTYPE: $
811	CODE:
812	RETVAL = max_outstanding;
813	max_outstanding = nreqs;
814
815	void
816	aio_open (pathname,flags,mode,callback=&PL_sv_undef)
817	SV * pathname
818	int flags
819	int mode
820	SV * callback
821	PROTOTYPE: $$$;$
822	CODE:
823	{
824	dREQ;
825
826	req->type = REQ_OPEN;
827	req->data = newSVsv (pathname);
828	req->dataptr = SvPVbyte_nolen (req->data);
829	req->fd = flags;
830	req->mode = mode;
831
832	send_req (req);
833	}
834
835	void
836	aio_close (fh,callback=&PL_sv_undef)
837	SV * fh
838	SV * callback
839	PROTOTYPE: $;$
840	ALIAS:
841	aio_close = REQ_CLOSE
842	aio_fsync = REQ_FSYNC
843	aio_fdatasync = REQ_FDATASYNC
844	CODE:
845	{
846	dREQ;
847
848	req->type = ix;
849	req->fh = newSVsv (fh);
850	req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
851
852	send_req (req);
853	}
854
855	void
856	aio_read (fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
857	SV * fh
858	UV offset
859	UV length
860	SV * data
861	UV dataoffset
862	SV * callback
863	ALIAS:
864	aio_read = REQ_READ
865	aio_write = REQ_WRITE
866	PROTOTYPE: $$$$$;$
867	CODE:
868	{
869	aio_req req;
870	STRLEN svlen;
871	char *svptr = SvPVbyte (data, svlen);
872
873	SvUPGRADE (data, SVt_PV);
874	SvPOK_on (data);
875
876	if (dataoffset < 0)
877	dataoffset += svlen;
878
879	if (dataoffset < 0 \|\| dataoffset > svlen)
880	croak ("data offset outside of string");
881
882	if (ix == REQ_WRITE)
883	{
884	/* write: check length and adjust. */
885	if (length < 0 \|\| length + dataoffset > svlen)
886	length = svlen - dataoffset;
887	}
888	else
889	{
890	/* read: grow scalar as necessary */
891	svptr = SvGROW (data, length + dataoffset);
892	}
893
894	if (length < 0)
895	croak ("length must not be negative");
896
897	{
898	dREQ;
899
900	req->type = ix;
901	req->fh = newSVsv (fh);
902	req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
903	: IoOFP (sv_2io (fh)));
904	req->offset = offset;
905	req->length = length;
906	req->data = SvREFCNT_inc (data);
907	req->dataptr = (char *)svptr + dataoffset;
908
909	if (!SvREADONLY (data))
910	{
911	SvREADONLY_on (data);
912	req->data2ptr = (void *)data;
913	}
914
915	send_req (req);
916	}
917	}
918
919	void
920	aio_sendfile (out_fh,in_fh,in_offset,length,callback=&PL_sv_undef)
921	SV * out_fh
922	SV * in_fh
923	UV in_offset
924	UV length
925	SV * callback
926	PROTOTYPE: $$$$;$
927	CODE:
928	{
929	dREQ;
930
931	req->type = REQ_SENDFILE;
932	req->fh = newSVsv (out_fh);
933	req->fd = PerlIO_fileno (IoIFP (sv_2io (out_fh)));
934	req->fh2 = newSVsv (in_fh);
935	req->fd2 = PerlIO_fileno (IoIFP (sv_2io (in_fh)));
936	req->offset = in_offset;
937	req->length = length;
938
939	send_req (req);
940	}
941
942	void
943	aio_readahead (fh,offset,length,callback=&PL_sv_undef)
944	SV * fh
945	UV offset
946	IV length
947	SV * callback
948	PROTOTYPE: $$$;$
949	CODE:
950	{
951	dREQ;
952
953	req->type = REQ_READAHEAD;
954	req->fh = newSVsv (fh);
955	req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
956	req->offset = offset;
957	req->length = length;
958
959	send_req (req);
960	}
961
962	void
963	aio_stat (fh_or_path,callback=&PL_sv_undef)
964	SV * fh_or_path
965	SV * callback
966	ALIAS:
967	aio_stat = REQ_STAT
968	aio_lstat = REQ_LSTAT
969	CODE:
970	{
971	dREQ;
972
973	New (0, req->statdata, 1, Stat_t);
974	if (!req->statdata)
975	{
976	free_req (req);
977	croak ("out of memory during aio_req->statdata allocation");
978	}
979
980	if (SvPOK (fh_or_path))
981	{
982	req->type = ix;
983	req->data = newSVsv (fh_or_path);
984	req->dataptr = SvPVbyte_nolen (req->data);
985	}
986	else
987	{
988	req->type = REQ_FSTAT;
989	req->fh = newSVsv (fh_or_path);
990	req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
991	}
992
993	send_req (req);
994	}
995
996	void
997	aio_unlink (pathname,callback=&PL_sv_undef)
998	SV * pathname
999	SV * callback
1000	ALIAS:
1001	aio_unlink = REQ_UNLINK
1002	aio_rmdir = REQ_RMDIR
1003	aio_readdir = REQ_READDIR
1004	CODE:
1005	{
1006	dREQ;
1007
1008	req->type = ix;
1009	req->data = newSVsv (pathname);
1010	req->dataptr = SvPVbyte_nolen (req->data);
1011
1012	send_req (req);
1013	}
1014
1015	void
1016	aio_link (oldpath,newpath,callback=&PL_sv_undef)
1017	SV * oldpath
1018	SV * newpath
1019	SV * callback
1020	ALIAS:
1021	aio_link = REQ_LINK
1022	aio_symlink = REQ_SYMLINK
1023	aio_rename = REQ_RENAME
1024	CODE:
1025	{
1026	dREQ;
1027
1028	req->type = ix;
1029	req->fh = newSVsv (oldpath);
1030	req->data2ptr = SvPVbyte_nolen (req->fh);
1031	req->data = newSVsv (newpath);
1032	req->dataptr = SvPVbyte_nolen (req->data);
1033
1034	send_req (req);
1035	}
1036
1037	void
1038	flush ()
1039	PROTOTYPE:
1040	CODE:
1041	while (nreqs)
1042	{
1043	poll_wait ();
1044	poll_cb ();
1045	}
1046
1047	void
1048	poll()
1049	PROTOTYPE:
1050	CODE:
1051	if (nreqs)
1052	{
1053	poll_wait ();
1054	poll_cb ();
1055	}
1056
1057	int
1058	poll_fileno()
1059	PROTOTYPE:
1060	CODE:
1061	RETVAL = respipe [0];
1062	OUTPUT:
1063	RETVAL
1064
1065	int
1066	poll_cb(...)
1067	PROTOTYPE:
1068	CODE:
1069	RETVAL = poll_cb ();
1070	OUTPUT:
1071	RETVAL
1072
1073	void
1074	poll_wait()
1075	PROTOTYPE:
1076	CODE:
1077	if (nreqs)
1078	poll_wait ();
1079
1080	int
1081	nreqs()
1082	PROTOTYPE:
1083	CODE:
1084	RETVAL = nreqs;
1085	OUTPUT:
1086	RETVAL
1087